Going diesel need not mean spending a lot of money. All five of these penny-pinching diesels come in comfortably under $30,000.

Diesel engines are pretty cool. Unlike conventional gasoline engines, diesel engines don’t use spark plugs, igniting fuel instead using super-high temperatures developed by compressing the air/fuel mixture. That high-temperature combustion contributes to a cleaner, more efficient burn of the fuel.

Even cooler, diesel packs about 12 percent more energy into a gallon than does gasoline, making it an excellent transportation fuel choice.

How much more efficient are diesel-powered cars than their gas-powered alternatives? In some cases, considerably so. The gasoline-powered 2015 Jetta S 1.8T scores an EPA estimated 34 mpg on the highway when equipped with a 6-speed manual transmission. That same Jetta in 2.0T TDI trim earns an EPA rating of 46 mpg on the highway. In this case, the diesel is 35 percent more efficient than the already-frugal gas-powered Jetta.

Yet, despite the obvious efficiency benefits of diesel-vehicle ownership, American shoppers are overwhelmingly sticking with gasoline-engine cars and trucks. In 2014, diesel vehicles comprised less than three percent of total new-vehicle sales, slightly outselling hybrid vehicles.

One concern shoppers may have is the cost of diesel ownership. Indeed, diesel-powered vehicles do cost more than their gas-powered alternatives. Typically, a diesel version of a given model will run $1500-$3000 more than a gasoline model, though the actual price difference is usually obfuscated by differing content and trim levels.

For shoppers who are thinking about a diesel-powered vehicle for their next car or truck but are concerned about the price, we have listed below the five cheapest diesels now available. Note that four of the five cars below are Volkswagen models. This should come as no surprise, as VW (and sister-brand Audi) products accounted for around 80 percent of total U.S. diesel sales last year.